Safety pressure vessel for carbonated beverages and the like



March 31, 1964 F. WELTY ETAL 3,127,049

SAFETY PRESSURE VESSEL FOR CARBONATED BEVERAGES AND THE LIKE Filed Sept.7, 1961 2 Sheets-Sheet l FRANK WELTY RAYMOND o. WELTY FIG. 5

BYMKK ATTOR EY March 31, 1964 WELTY ETAL 3,127,049

SAFE IY PRESSURE VESSEL FOR CARBONATED BEVERAGES AND THE LIKE FiledSept. 7, 1961 2 Sheets-Sheet 2 INVENTOKS FRANK W ELT Y B RAYMOND o.WELTY 1 a ATTORNEY United States Patent 3,127,049 SAFETY PRESSURE VESSELFOR CARBONATED BEVERAGES AND THE LIKE Frank Weity, 4962 Lockwood Blvd,and Raymond D. Welty, 4307 Lake Road, both of Youngstown, Ohio FiledSept. 7, 1961, Ser. No. 136,575 Claims. (Cl. 220-44)) This inventionrelates to a safety closure cap structure for pressure vessels and moreparticularly to an improved and simplified arrangement for protecting apressure-filled vessel against rupture due to excessive pressure. Theprimary object of the invention is to provide this safety feature on apressure vessel without adding to the complexity or cost of the vessel,and in accordance with this invention this object is accomplished by soconstructing the conventional closure cap structure of the vessel thatthe cap itself and its sealing means act as the safety valve to relievethe excess pressure.

The invention is specifically intended to protect handlers and/ or usersof transportable gas-filled pressure vessels against injury as mayresult from explosive rupture thereof. In the bulk distribution ofbeverages, for example, it is now common practice to fill a closedcontainer with a carbonated beverage against a back pressure supplied bya carbonating gas. At the place of consumption the container isconnected to a source of carbonating gas under pressure to expel ordispense the beverage to a faucet while maintaining the desired degreeof carbonation in the beverage remaining in the container. Normally,this gas source is a high-pressure cylinder filled with compressed gasto which is connected a pressure reducing and regulating valve. If thisvalve is improperly adjusted or becomes defective, the beveragecontainer may become dangerously subjected to excessive gas pressurewith consequent explosive potentialities. It is accordingly highlydesirable to provide the container or vessel with a safety valvefeature.

Beverage containers of the kind mentioned above are used in largequantities and are often subjected to rough handling. It is thereforedesirable that the safety valve feature be imple, inexpensive, andinherently rugged to the extent that it cannot become inoperativebecause of rough handling. Further, it must be fail-safe in nature andof a character incapable of being tampered with.

This invention meets all the above requirements by so constructing thewide-mouth closure cap assembly universally used on bulk-beveragecontainers in such manner that the assembly itself inherently operatesas a safety valve. First, the design of the sealing ring used and itsrelation to surfaces of the container and cap is such that unless thecap is fully applied or in full on position it will release the pressurein the container. Secondly, the cap retaining means is provided with ayieldable link or element whereby abnormal pressures acting on the capwill force the cap outwardly a sufiicient distance to release thepressure while yet retaining the cap on the container.

The manner in which the above objects are accomplished by this inventionwill become apparent upon consideration of the following specificationand accompanying drawing wherein there is disclosed preferredembodiments of the invention.

In the drawing:

FIGURE 1 is a vertical section of a safety closure cap assemblyconstructed in accordance with the teachings of our invention;

FIGURES 2 and 3 are elevational views of a cap securing element used inthe assembly of FIGURE 1 before and after the application of excessivepressure to the cap which had been secured thereby;

' ring used in the assembly of FIGURE 1;

FIGURE 5 is an elevation of a modified form of cap securing device whichmay be used in carrying out the principles of our invention;

FIGURES 6 and 7 are plan views of the container opening and the capmember, respectively of a further embodi ment of the invention; and

FIGURES 8 and 9 are elevation and sectional views, respectively, of theopening neck structure of FIGURE 6.

Referring first to FIGURES 1-5, reference numeral 10 designates aportion of the top wall of the pressure vessel or container to which theinvention is applied. When used for beverages, such containers arecommonly made of stainless steel and have large openings to facilitatecleaning and inspection of the inner surfaces thereof. Commonly, theseopenings are formed with an upwardly directed annular projection of aportion of the top wall of the container, such as shown at 11 in thedrawing. This annular projection is used to seal and secure a closurecap, with the securing means being of the quick-disconnect type wherebythe closure cap may be quickly applied to and removed from thecontainer.

In our construction, the free end portion of the annular projection 11.is flared outwardly as shown at 12 and the closure cap 13 is formed withan integral inwardly opening annular channel 14 which receives the majorpart of the annular projection 11. The cap member 13 is dieformed from asingle disc of stainless steel and, as shown in FIGURE 1, the annularchannel aforementioned provides a cylindrical wall 15 radially inward ofand concentric with the flaring 12. The channel also provides an endwall 16 which spans the annular space between the wall 15 and theflaring 12.

To effect a fluid-tight seal between the side wall 11 forming theopening into the container and the closure cap 13 we provide an annularresilient and deformable sealing ring 17 which may be molded fromneoprene rubber. As shown in FIGURES 1 and 4, the ring 17 is generallyU-shaped in cross section to provide concentric radially inner and outerbands integraliy connected by a body portion 18. In use, the outer bandof ring 17 overlies the inner surface of flaring 12 in dependingrelation while the inner band of the ring overlies the cylindrical wall15 of the cap member 13 with the body portion 18 of the ring restingagainst the inner surface of the annular end wall 16 of the cap member.To provide sensitivity in the sealing action the body portion 18 of ring1'7 is formed with a continuous rib 19 on its top surface and for thissame purpose as well as for an additional purpose to be explained belowthe free edges of the concentric bands of the ring are outwardly beadedas shown at 20. It should be apparent that with the sealing ring 17installed in the manner shown in FIGURE 1 and with the cap tightlyapplied to the annular projection 11 whereby the sealing ring iscompressed, a continuous effective seal is formed between the flaring 12and the cap member to prevent the escape of fluid, either gas or liquid,from the container.

To provide the quick-detachable interconnection between the cap and theprojection 11 and to provide means for tightening the cap onto theprojection, we provide a series of circumferentially spaced cams on theouter surface of the projection 11 for engagement by lugs extendinginwardly from the outer cylindrical wall of the cap member 13. Asindicated in FIGURE 1 these lugs may be simply inwardly bent portions ofthis outer cylindrical wall, as shown at 21. In the form of theinvention shown in FIGURES 1-3, the cams are formed from strips of metal22 which are suitably contoured or bent to fit snugly around thecurvature of the outer surface of projection 11. Strips 22 are formed atone end with an inte gral tab 23 which is rigidly welded to the metal ofwall 11 and the other end of each strip is bent downwardly as shown at24 and this other end portion is also rigidly welded to the wall 11.Each of the strips 22 is formed with an entering portion 25 ofsubstantial length and of generally horizontal disposition whichterminates in a steep cam portion 26. The steep cam portions 26 areprovided to insure that the sealing ring 17 will be compressed apredetermined amount sufficient to insure the required sealing action.The steep cam portions 26 terminate in elongated slightly-inclinedterminal portions 27 by which the final tightening of the cap member isaccomplished and by which the cap member is held against accidentalrotation in an off direction. The latter characteristic results from theflatness of the portions 27 and resultant friction as will beunderstood.

In accordance with the principles of our invention, portions 23, 24 and25 of the strips 22 may be rigidly and continuously welded to the metalof projection 11 but portions 26 and 27 are either not welded or areonly lightly welded at spaced points so that these portions may bendupwardly upon the application of excessive internal pressure acting onthe cap member. What extent of these portions 26 and 27 is leftunattached will, of course, be determined by the thickness and strengthof the strips 22, the number of strips used, the diameter of the cap,and the maximum pressure desired in the container.

Referring again to the sealing ring and its manner of use, it will beobvious that so long as the cap member is tightly applied to thecontainer the configuration of the ring provides a self-sealing elfectso that any pressure Within the capacity of the container may beretained. However, if the cap rises with respect to the container thering will open up to the shape shown in FIGURE 4 whereby only a linecontact will remain between the flaring 12 and the ring. This linecontact results from the head 20 on the outer band of the ring, and thebead has the further function of limiting the further radially outwardexpansion or diameter growth of this line contact. At this point highpressure cannot be retained and any abnormal pressures applied to thecontainer will be bled off. However, the bead does provide a sensitiveseal so that upon release of this excess pressure and the resultantlowering or tightening of the cap by the spring action of the strips 22will re-establish the seal and prevent spoilage of the beverage or othercontents of the container.

In the embodiment of the invention shown in FIG- URE 5, the cams areprovided by radially outward flanges of a ring 28 which is welded orotherwise suitably secured to the neck of projection 11 of the container10. To provide the safety feature involved herein either the ring itselfmay be slit or deeply scored at locations indicated by the doted line 29in FIGURE or by slitting or scoring the flanges themselves at similarlocations. The operation of this embodiment is precisely the same asthat described above in connection with FIGURES 1-4.

In the embodiment of the invention illustrated in FIGURES 6-9 thecap-locking cams are integrally formed of the sheet metal of thecontainer by providing excess metal outwardly of the flare 12', whichexcess metal is rolled downwardly to form a skirt indicated generally byreference numeral 30. This exces metal or skirt is notched atcircumferentially spaced points as shown at 31 to allow vertical passageof the lugs 21' of the closure cap. It should be understood that theclosure cap of FIGURE 7 is substantially identical with the cap ofFIGURE 1, and that the same sealing ring as shown in FIGURES 1 and 4will be used in the embodiment of FIGURES 69.

Skirt 30 is die-cut to provide three circumferentially spaced cams eachconsisting of a flat entering portion 32, a steep intermediate portion33, a slightly inclined locking portion 34, and a stop 35. 'Cam portions33 insure that the sealing ring will be properly compressed before thelugs 21' enter onto the slightly inclined locking portions 34. They havethe further function, which is also true of the first describedembodiments, of retaining the cap against being blown upward at time ofremoval by any residual gas pressure which may be in the container. Byallowing the lugs 21 to raise a substantial distance to the entryportions 32, the sealing ring is fully released to allow theinstantaneous release of any such residual pressure. Thus, even thoughthe cap be removed quickly with a continuous rotating motion, the upwardforce on the cap will be dissipated before the lugs 21 run off the entryend of cam portions 32.

In the embodiments of the invention shown in FIG- URES 6 thru 9, thegauge of the metal of the container is such that upon the appearance ofdangerously high pressure in the container the skirt 30 will be deformedto release this high pressure. Such deformation will comprise therocking inward of portions of the skirt (or cams) and the flare 12adjacent the points of contact of the lugs 21 with the skirt. Thiscauses the flare 12' to bow outwardly in the regions of the slots 31 andthereby the flare is made out-of-round and entirely incapable ofmaintaining a seal with the sealing ring. In actual practice, the gaugeof the metal used is determined by test. The deformation under highpressures is rather severe in the embodiment in FIGURES 6-9, and it isnot intended that these deformed containers will be reused.

It should now be apparent that we have provided an improved safetypressure vessel for containing and dispensing carbonated beverages andthe like which accomplishes the objects initially set out. By providingfor the limited yet retained outward movement of the normally requiredclosure cap for such vessels or containers and so constructing thesealing ring as to relieve the excessive pressure upon such limitedoutward movement of the cap, we are able to provide the saefty valvefeature without adding components or increasing the cost of the vesselor container. Further, the nature of this safety feature is such that itcannot be tampered with and is extremely rugged and durable to withstandthe severe conditions of handling service to which this type ofequipment is normally subjected.

It will be readily apparent to those skilled in the art that specificmeans, other than those herein disclosed, may be employed to allow thepressure cap to have a limited outward yet definitely retained outwardmovement to relieve excess pressure in the container. For example, theflanges forming the lock-on cams engaged by the lugs of the cap and ofthe general style used in the first described embodiments may be made ofsuitable material and dimension to be deformable and thus themselvesserve as the yieldable means allowing the cap to have limited outwardmovement.

Since changes may be made in the details of the essential components ofthe safety closure cap structure herein disclosed without departing ofthe spirit and scope of the invention, reference should be had to theappended claims in determining the scope of the invention.

We claim:

1. A safety cap structure for a pressure vessel having a wide-mouthedopening defined by an annular projection of its wall and in which thefree end portion of said projection is flared outwardly to provide aninternal conical sealing surface comprising a flanged disc-like capadapted to be received over said outwardly flared end of said annularprojection with the flange thereof concentric with and radially outwardof said annular projection, said cap having an inner annular sealingsurface concentric with but radially inward of said conical sealingsurface, a plurality of circumferentially extending andcircumferentially spaced lugs carried by said annular projection andpositioned on the outside thereof between the outer end of the flaredportion thereof and the body of said container; each of said lugs havinga flat portion extending generally parallel with the said end of saidflared portion of said projection, an intermediate portion inclinedsteeply toward the body portion of said container, and an end portionslightly inclined toward said body portion of the container, a sealingring which is of inverted U-shape in radial crosssection having sidewall portions lying against said conical and annular sealing surfaces,the flange on said cap having radially inward directed detents to engageunderneath said lugs and to compress said sealing ring upon rotation ofsaid cap on said annular projection in one direction and the consequentmovement of the cap toward the body portion of said container, thearrangement being such that said sealing ring is ineffectual when saiddetents are under the flat portions of said lugs but is operative toeffect a self-sealing action when said detents are under the slightlyinclined end portions of said lugs when said slightly inclinded portionsare in their normal positions with respect to said conical sealingsurface, and said slightly inclined portions of said lugs beingyieldable in an outward direction parallel With the axis of said annularprojection where-by upon the appearance of excessive pressure within thecontainer said cap can lift off slightly to render said sealing ringineffectual and thus permit the release of excess pressure in saidcontainer.

2. Structure according to claim 1 further characterized in that said caphas a cylindrieally-shaped Wall radially inward of said flared portionand an annular end wall in the end projection of said flared portion toprovide an additional bearing for said sealing ring.

3. Structure according to claim 1 further characterized in that the freeedges of the side walls of said ring are each formed with a continuousintegral bead having normal continuous contact with said annular andconical surfaces, said beads having only line contact with said annularand conical surfaces when said cap is moved to outward yet retainedposition by excessive pressure in said vessel which line contact isinsufiicient to retain said pressure, and said beads also acting tolimit the change in diameters of said free edges of said side walls.

4. Structure according to claim 1 further characterized in that saidlugs each comprises an elongated metal strip curved about saidprojection, said metal strips being solidly secured to said projectiononly at spaced points along each strip to allow said slightly inclinedportions of the lugs to be bent out of position upon the application ofexcessive vessel pressure to said cap.

5. Structure according to claim 1 further characterized in that saidconical sealing surface on said projection is provided by said outwardlyflaring portion of said projection and in that said lugs dependintegrally from a skirt formed integrally with and rolled over from theouter edge of said flaring portion.

References Cited in the file of this patent UNITED STATES PATENTS2,266,314 Eshbaugh Dec. 16, 1941 2,513,458 Dion July 4, 1950 2,549,387Richeson Apr. 17, 1951 2,948,431 Kuhn Aug. 9, 1960 3,042,246 Welty et alJuly 3, 1962

1. A SAFETY CAP STRUCTURE FOR A PRESSURE VESSEL HAVING A WIDE-MOUTHEDOPENING DEFINED BY AN ANNULAR PROJECTION OF ITS WALL AND IN WHICH THEFREE END PORTION OF SAID PROJECTION IS FLARED OUTWARDLY TO PROVIDE ANINTERNAL CONICAL SEALING SURFACE COMPRISING A FLANGED DISC-LIKE CAPADAPTED TO BE RECEIVED OVER SAID OUTWARDLY FLARED END OF SAID ANNULARPROJECTION WITH THE FLANGE THEREOF CONCENTRIC WITH AND RADIALLY OUTWARDOF SAID ANNULAR PROJECTION, SAID CAP HAVING AN INNER ANNULAR SEALINGSURFACE CONCENTRIC WITH BUT RADIALLY INWARD OF SAID CONICAL SEALINGSURFACE, A PLURALITY OF CIRCUMFERENTIALLY EXTENDING ANDCIRCUMFERENTIALLY SPACED LUGS CARRIED BY SAID ANNULAR PROJECTION ANDPOSITIONED ON THE OUTSIDE THEREOF BETWEEN THE OUTER END OF THE FLAREDPORTION THEREOF AND THE BODY OF SAID CONTAINER; EACH OF SAID LUGS HAVINGA FLAT PORTION EXTENDING GENERALLY PARALLEL WITH THE SAID END OF SAIDFLARED PORTION OF SAID PROJECTION, AN INTERMEDIATE PORTION INCLINEDSTEEPLY TOWARD THE BODY PORTION OF SAID CONTAINER, AND AN END PORTIONSLIGHTLY INCLINED TOWARD SAID BODY PORTION OF THE CONTAINER, A SEALINGRING WHICH IS OF INVERTED U-SHAPE IN RADIAL CROSSSECTION HAVING SIDEWALL PORTIONS LYING AGAINST SAID CONICAL AND ANNULAR SEALING SURFACES,THE FLANGE ON SAID CAP HAVING RADIALLY INWARD DIRECTED DETENTS TO ENGAGEUNDERNEATH SAID LUGS AND TO COMPRESS SAID SEALING RING UPON ROTATION OFSAID CAP ON SAID ANNULAR PROJECTION IN ONE DIRECTION AND THE CONSEQUENTMOVEMENT OF THE CAP TOWARD THE BODY PORTION OF SAID CONTAINER, THEARRANGEMENT BEING SUCH THAT SAID SEALING RING IS INEFFECTUAL WHEN SAIDDETENTS ARE UNDER THE FLAT PORTIONS OF SAID LUGS BUT IS OPERATIVE TOEFFECT A SELF-SEALING ACTION WHEN SAID DETENTS ARE UNDER THE SLIGHTLYINCLINED END PORTIONS OF SAID LUGS WHEN SAID SLIGHTLY INCLINED PORTIONSARE IN THEIR NORMAL POSITIONS WITH RESPECT TO SAID CONICAL SEALINGSURFACE, AND SAID SLIGHTLY INCLINED PORTIONS OF SAID LUGS BEINGYIELDABLE IN AN OUTWARD DIRECTION PARALLEL WITH THE AXIS OF SAID ANNULARPROJECTION WHEREBY UPON THE APPEARANCE OF EXCESSIVE PRESSURE WITHIN THECONTAINER SAID CAP CAN LIFT OFF SLIGHTLY TO RENDER SAID SEALING RINGINEFFECTUAL AND THUS PERMIT THE RELEASE OF EXCESS PRESSURE IN SAIDCONTAINER.